This invention relates to a mount for supporting a suspension strut assembly on a vehicle body. The strut assembly includes a coil spring engaged at its upper end by an upper spring seat disc and a shock absorber having an upwardly extending piston rod. The upper spring seat disc, together with the upper end of the shock absorber piston rod, is supported on the vehicle body by means of a common, removable rubber-and-metal antivibration unit. The vehicle body is provided with an opening in the zone where the strut assembly is attached. The zone is hereafter referred to as "location of support". The piston rod which is secured to the antivibration unit by a nut, is accessible through the opening. An outer metal flange of the antivibration unit is tensioned from below by means of securing screws against the rim zones of the opening.
An arrangement of the above-outlined type is known and is disclosed, for example, in German Accepted Published Patent Application (Auslegeschrift) No. 2,435,723 and German Laid-Open Application (Offenlegungsschrift) No. 2,447,821.
Mounts of this type provide for a simple removal of a faulty shock absorber. Thus, it suffices to loosen a few securing screws and to pull the faulty shock absorber simply upwardly through the opening in the vehicle body without the need of removing or entirely disassembling the other wheel-guiding components (particularly the wheel-guiding portion) of the suspension strut assembly.
According to the known mount shown in FIG. 3 of the above-noted German Accepted Published Patent Application No. 2,435,723, the opening of the vehicle body at the location of support has an approximately circular contour with two diametrically oppositely located, radially outwardly oriented tab-shaped enlargements. The outer metal flange of the antivibration unit which is to be tightened from below against the rim of the opening also has an approximately circular external contour with two diametrically opposite, radially outwardly extending, tab-shaped projections for the securing screw. The diameter of the circular contour of the metal flange is slightly smaller than the diameter of the circular contour of the opening. Similarly, the contour of the tab-shaped projections is somewhat smaller than the contour of the tab-shaped enlargements of the opening. In the assembled condition the tab-shaped projections of the metal flange form an angle of approximately 90.degree. with the tab-shaped enlargements of the opening. For removing the shock absorber or parts thereof, the antivibration unit can be removed outwardly together with the shock absorber piston rod after loosening the securing screw and a subsequent rotation of the antivibration mount about the above-noted angle of approximately 90.degree.. Since the relatively large vertical forces which affect the suspension strut assembly are transmitted to the vehicle body exclusively through the tab-shaped projections, the latter have to be of sufficiently large dimension to maintain a proper overlap between the metal flange of the antivibration unit and the vehicle body. Tab-shaped projections of large dimension, however, require correspondingly large tab-shaped extensions in the opening; this, in turn, reduces the strength of the vehicle body in the location of support. Thus, in such a construction it is thus necessary to find a compromise between the dimensions of the tab-shaped projections and the dimensions of the tab-shaped extensions of the opening.
According to another known arrangement, as shown in FIG. 4 of German Laid-Open Application No. 2,447,821, at the location of support there is provided, in the vehicle body, a circular opening of relatively large diameter against the rim of which the outer metal flange of the antivibration unit is tightened with the interposition of an intermediate flange. The overlaps between the intermediate flange, on the one hand, and the rim of the opening and, respectively, the metal flange, on the other hand, are correspondingly large. Since the intermediate flange is tightened from above against the rim of the opening, the vertical forces introduced by the suspension strut assembly have to be transmitted through the securing screws between the intermediate flange and the vehicle body.